Counterweight for stands

ABSTRACT

The invention relates to a support stand with a carrying arm ( 3 ), a standard ( 4 ), and a support stand foot ( 6 ), where a functional housing ( 5 ) serving as counterbalance is secured to the standard ( 4 ). The dimensions of the foot ( 6 ) of the support stand are such that said foot exhibits a preferred direction of support ( 15 ) that affords increased security against tipping and exhibits a permitted area of support lateral to the preferred direction of support ( 15 ). The swivel capability of the carrying arm ( 3 ) on a horizontal plane is limited by a stop ( 9 ), in such a way that the carrying arm ( 3 ) cannot swivel into a position perpendicular to the direction of support and cannot swivel outside of the permitted area of support.

BACKGROUND OF THE INVENTION

The invention relates to a support stand, particularly a support standfor an operating microscope. Alongside expensive structures withcounterbalances for support stands, there are also simpler supportstructures in the area of operating microscopy which manage withoutvertical parallel supports and which use a gas-loaded spring, or thelike, as a counterweight for holding the operating microscope inbalance. Reference is made in this regard to the applicant's patent U.S.Pat. No. 5,213,293. This kind of relatively simple support stand isdesigned in such a way that the stand foot has enough stability for thestand not to tip when conventional operating microscopes are employed.

Known from U.S. Pat. No. 5,257,998 is a support stand for a stereotaxissystem that exhibits a support stand foot and a standard assigned to it.A carrying arm with a counterbalance is secured to the stand. Thecounterbalance is equipped as a functional housing containing differentelectrical structural components. The large swivel area of the standgives the foot a symmetrical design, and the foot is consequently verylarge and heavy.

SUMMARY OF THE INVENTION

The invention is based on the problem of modifying the stand design in away that permits it to carry heavier weights in the area of the load,particularly the area of the operating microscope, and/or to give thefoot of the stand a lighter design.

A certain problem arises with stand feet: the further the feet projectlaterally into space, the more they hinder the personnel. An attempt istherefore made to limit the width of the feet. A further task of thepresent invention is to meet the need for a lighter foot.

These problems are solved by the features indicated in thecharacterizing portion of patent claim 1.

The combination of features shown in claim 1 yields a design that issimple, provides a practical counterbalance, and exhibits a reducedtendency to tip. Elaborations of the invention emerge from the dependentclaims. Together with the drawings, the specialist will see a novelstand design that does justice both to the problems addressed by theinvention and the need to equip conventional stands with electronicequipment.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description of the figures involves all the figures.Identical structural parts have identical reference numbers; differentbut functionally comparable parts have identical reference numbers butdifferent secondary indices.

Shown are:

FIG. 1: a variation in side view, in which the carrying arm can berotated around a swivel axis;

FIG. 2: a top view of the structure shown in FIG. 1;

FIG. 3: a variation of the same in side view;

FIG. 4: a section through the structure of FIG. 3 along line IV—IV; and

FIG. 5: a view similar to that of FIG. 3, showing a variation wherein anelectronic control box is supported by a foot of the invention.

Not shown in the figures are certain supporting mechanisms like gaspressure springs or like, such as those known from the referenced U.S.Pat. No. 5,213,293. Express reference is therefore made to the contentof this publication for the purpose of a more detailed design of thecarrying arm support structure of the stand according to the invention.The design according to the invention is not restricted to suchelaborations, however.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The support stand according to the invention has a standard which bearsa carrying arm 3 aor 3 b. A control box 5 that is connected in rigidfashion to the standard 4 a or 4 b serves as a counterbalance for aweight mounted on the swivel arm, for example, an operating microscope1. The control box 5 might contain, for example, electronic components,power supply equipment, any equipment needed for illumination, etc.,and, if required, additional weights 14.

FIG. 1 shows an embodiment in which the carrying arm 3 a can be rotatedaround a swivel axis 8 on the standard 4 a, see the circular doublearrow 6. A stop 9 a limits the lateral mobility of the carrying arm 3 ain both directions. This assures that the carrying arm 3 a cannot swivelinto a position that runs athwart the preferred direction of support 15of the stand foot 6 a. The foot 6 a is designed in a way such that itoffers comparatively little security against tipping in a directionperpendicular to the preferred support direction 15. This embodiment iscut along section I—I in FIG. 2.

FIG. 2 shows the structure of FIG. 1 in top view. It is clear from thefigure that the foot 6 a has an H shape and thus extends considerablyfurther in the direction of support 15 than in the direction 17perpendicular thereto. As compared to a square or a circle, the foot canthus have a light weight while providing an unlimited degree of securityagainst tipping in the direction of support 15.

FIGS. 3 and 4 show a variant in which the carrying arm 3 b and thestandard 4 b are rigidly connected in turning fashion. FIG. 3 shows asection along line III—III in FIG. 4. With this structure, the swivelmovement suggested by the double arrow 16 on a horizontal plane isguaranteed by the rotating capability of the standard 4 b within thefoot 6 b. To this end, the standard 4 b is inserted into a hole in thefoot 6 b and is supported with respect to the foot by a support ring 10.At least one stop pin 11 slides within a stop groove 13 (13 a, 13 b) tolimit the lateral swiveling movement of the standard 4 b. Serving tomount the standard 4 b within the foot 6 b are, for example, mountingslits 12 which permit the standard 4 b to sink into the foot 6 b alongwith the stop pin(s) 11.

The two depicted variants do not show a potential swivel motion of thecarrying arm 3 a on a vertical plane. This kind of movement, and thestructural measures required to execute it, are known to the specialistin a variety of ways. Reference is made, for example, to the alreadymentioned U.S. Pat. No. 5,213,293 and the applicant's support standbased on that publication.

The core of the present invention rests in the combination of a rigidcounterbalance, specifically one containing functional parts, positionedon a standard, and a stop which limits the swivel motion of the carryingarm on a horizontal plane, ideally in symmetrical fashion relative tothe preferred direction of support.

List of Reference Numerals

1 operating microscope

2 microscope support

3 a, b carrying arm

4 a, b standard

5 control box/housing

6 a, b stand foot

7 roller or supporting foot

8 swivel axis

9 a, b stop

10 support ring

11 stop pin

12 mounting slit

13 a, b stop groove

14 weights

15 preferred direction of support

16 double arrow

17 perpendicular direction

What is claimed is:
 1. A support stand comprising: a foot elongated in achosen direction of support; a standard extending only along a verticalaxis from said foot; a carrying arm mounted on said standard, saidcarrying arm being rotatable in a horizontal plane about a swivel axiscoinciding with said vertical axis of said standard; a functionalhousing secured to said standard such that the weight of said functionalhousing and any items therein has a line of action offset from saidvertical axis of said standard to act as a counterbalance to saidcarrying arm and loads carried thereby; and stop means for preventingsaid carrying arm from being rotated to a position wherein said carryingarm extends in a direction generally perpendicular to said direction ofsupport.
 2. The support stand according to claim 1, wherein saidstandard and said carrying arm rotate together about said swivel axis,and said stop means acts between said standard and said foot.
 3. Thesupport stand according to claim 1, wherein said carrying arm rotatesrelative to said standard about said swivel axis, and said stop meansacts between said carrying arm and said standard.
 4. The support standaccording to claim 1, further comprising an electronic power supply andcontrol system enclosed by said housing for operating said stand.
 5. Thesupport stand according to claim 1, further comprising an electronicpower supply and control system enclosed by said housing for operating amicroscope supported by said stand.
 6. The support stand according toclaim 1, further comprising additional counterweight enclosed by saidhousing for counterbalancing said carrying arm and loads carriedthereby.
 7. The support stand according to claim 1, further comprising aspring for supporting said carrying arm.
 8. The support stand accordingto claim 1, wherein said stop means defines a swivel area for saidcarrying arm which is symmetrical about said direction of support. 9.The support stand according to claim 1, wherein said foot extendsfurther in said direction of support than in a direction perpendicularto said direction of support.
 10. The support stand according to claim1, wherein said housing is supported by said foot.
 11. A surgicalapparatus comprising, in combination: a support stand including a footelongated in a direction of support, a standard extending verticallyfrom said foot, a carrying arm connected to said standard, said carryingarm being rotatable in a horizontal plane about a swivel axis, afunctional housing secured to said standard, and stop means forpreventing said carrying arm from being rotated to a position whereinsaid carrying arm extends in a direction generally perpendicular to saiddirection of support; and a surgical microscope carried by said carryingarm.